T Cells

• How does Cell Mediated Immunity begin?

  Antigen Presenting Cell
• What are the 4 main types of APC?

  • Phagocytes
  • Body Cells
  • Transplanted Cells
  • Cancer Cells
• What decides what specific immune response is used?

  Lymophocytes (T Cells and B Cells)
• What do T Cells only respond to?

  Antigens on the cell surface membrane, not any solutions or pathogens
• What is the Immune Response? (Part 1)

  1. Pathogen infects organism, has antigens
  2. Macrophages ingests antigen and displays portion on its surface
  3. Helper T Cells recognise antigen on the surface of macrophage when its receptors fit exactly onto the antigens
  4. Attachment of these receptors to antigens activate Cytoxic T Cells and B Cells
  5. Cytoxic T Cells divide rapidly by mitosis to form many clones
• What do cloned T Cells do?

  • Activate Cytoxic T Cells
  • Develop into memory cells
  • Stimulate phagocytes to engulf pathogens
  • Stimulate B Cells to divide and secrete antibodies
• What do active Cytoxic T cells do?

  Kill infected cells by producing a protein called Perforin
• What does Perforin do?

  Makes holes in the cell surface membrane of the infected cell so that it becomes more permeable and die